CVE-2025-40170: net: use dst_dev_rcu() in sk_setup_caps()

highCVSS 8.1CVE-2025-40170

CSIRTS triage

vendor: Linux product: Linux Kernel Memory corruption

What: Incorrect use of dst_dev() instead of dst_dev_rcu() in sk_setup_caps() causes potential use-after-free or data race.
Who is affected: Systems running affected Linux kernel versions with network packet processing under concurrent load.
Urgency: High; CVSS 8.1 indicates significant memory safety impact that could lead to crash or code execution.
Action: Apply kernel patch that corrects sk_setup_caps() to use dst_dev_rcu() or upgrade to patched kernel version.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 8.1
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-40170

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2025-401700.14% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 4% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2025-40170	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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